“Flightplan” is well made enough that it’s entertaining for most of its length. Granted, it’s basically “Panic Room” with wings—it even stars Jodie Foster as another terrified mom—but director Robert Schwentke, a German making his American debut here, keeps the suspense going from almost the opening scene. He matches the increase in tension to Foster’s skilled performance so neatly that our emotions keep pace with hers.

Unfortunately, however, it turns out to be driven by one of those stupid, only-in-a-movie schemes that require absolutely everything to go precisely the way the conspirators intend. The least slip and their carefully-laid plans would waft away like so much smoke—which is basically what they are. Here, for example, it is absolutely required that not a single passenger or flight attendant notices Foster’s six-year-old daughter. There are playful, noisy kids seated a row away; people walk up and down the aisles frequently; when boarding the plane, some passengers would have had to walk directly by the little girl. And yet nobody notices her.

The result is that the film runs out of credibility well before the plane runs out of air. In a sense, what happens in the last half hour or so is unimportant because by that time believability has been trampled under foot.

It’s also a little hard to accept that Foster is an American airline propulsion engineer living in Berlin. She has to be in order to pull off some of her own counter-plans. Also, one big visual idea is shamelessly swiped from Alfred Hitchcock’s classic “The Lady Vanishes,” although the movie is not especially Hitchcockian otherwise.

The script by Petra Dowling and Billy Ray must have dazzled Brian Grazer of Imagine Films; he’s been trying to get this one launched for some time. Presumably, the element that caught his eye is the basic setup. I don’t think her first name is spoken in the movie, but Foster plays Kyle Pratt, as mentioned, living in Berlin. There are some confusing flashbacks at the beginning, but we learn her husband fell to his death off the roof of their building. Now she and her six-year-old daughter Julia (Marlene Lawston) are accompanying the husband’s coffin back to America, the first visit for the child. Kyle’s nerves are understandably frayed, and she’s a bit overprotective of Julia even before they board the supercolossal airliner, a fictional E-474.

The immense plane is almost another character in the movie, which except for brief opening and closing scenes, is set entirely on the plane. It’s a huge monster with two decks of plentiful seating, a lounge and other amenities. Every seat features its own video screen; it’s surprising there isn’t a bowling alley. Since Kyle is an airplane expert, she knows about the several galleys and just how much extra space—other than the passenger compartments—that this plane contains. The script gets her into almost all of the various areas of the airliner.

Kyle and Julia are the first passengers aboard the flight, which is
filled but not to capacity. The child is still troubled by the
unexpected death of her father; Kyle is, too, but has to try to
maintain Julia’s spirits. Soon after the seat belt sign goes off, the
two move to vacant rows and stretch out to sleep.

When Kyle awakes, Julia is gone. No one has seen her, and in fact, one
of the flight attendants, Stephanie (Kate Beahan), says she thought
Kyle was alone when she boarded. Another attendant, Fiona (Erika
Christensen), is less certain. However, the flight manifest shows no
sign of Julia Pratt, and Kyle can’t locate her daughter’s boarding pass.

Understandably, Kyle starts raising a fuss, which leads to the
involvement of so-far friendly Gene Carson (Peter Sarsgaard), who
reveals himself as an air marshal. The more agitated Kyle becomes, the
less the others, including flight captain Rich (Sean Bean), are
inclined to believe her. Eventually, this leads to Kyle dashing about
the plane, getting into all kinds of areas, and trying to get Rich and
the others do do what she wants, whether they believe her or not.

The trouble with a movie like this is that it’s all setup. The premise
is established early on, but then the story stalls; it simply does not
realistically build beyond its overly familiar premise. The central
idea is one of the earliest urban legends: a pair of people (usually
mother and daughter) check into a hotel, taking separate rooms. The
next day one can’t find the other; asking at the desk produces only
“I’m sorry, madam, but when you checked in, you were alone.” Several
films have been based on this premise; it was even part of “The Kiss of
the Vampire,” a Hammer movie I watched the day I saw “Flightplan.”

Always, but ALWAYS, it turns out that our central character was right
all along and that there was a sinister plot to pretend the missing
person ever existed. And always, but ALWAYS, the central problem with
these stories is that we, the audience, have already seen the person
who disappears, so we know for sure that there is indeed a sinister
scheme. It would be interesting if one of these began with the
disappearance, not before, but so far I don’t recall having seen a
movie with that idea.

Director Schwentke seems to have all the skills necessary for movie of
this type. He shoots everything very low-key—this is a remarkably dark
movie—but he handles the confined areas of the plane with aplomb and
visual variety. (Even a plane this size is confined.) Suspense builds,
the actors do their stuff, and it’s all tense and exciting enough to be
entertaining for most of its length. He tries a few ideas that don’t
work: in her bedroom, Julia has a lamp with a rotating shade—but the
images it casts on the walls couldn’t possibly have been made by the
shade we see. Most viewers won’t notice this; those who do will be
irked by it and distracted from the story.

A few ideas are thrown in that, however contemporary, are intrusive and
even insulting. There are a few Arabs on the plane; Kyle fixes on them
as likely suspects near the beginning because, she says, she saw two of
them in the rooms across from hers in Berlin. The audience may very
well blurt out a collective “Huh!?” at that point, because WE didn’t
see them—and we’re supposedly experiencing the movie mostly from Kyle’s
point of view. A burly American passenger remains convinced that the
Arabs are the bad guys, and occasionally tries to do something about
it. This may be accurate in reflecting the tensions of our time, but
it’s also distracting and intrusive. (There’s also a key casting error,
but it’s difficult to describe it without revealing too much of the
plot.)

Jodie Foster doesn’t make very many movies these days, being busy as a
real-life mother. It’s a shame that she chose to make a movie so
similar to one of her recent films, and one that has so many holes in
its plot. (“Panic Room,” though not significantly better, at least held
together.) It’s like harnessing a race horse to a plough. You get the
job done, but the race horse is capable of so much more.